00:01
For this problem, to begin, we know that the call center receives an average of 3 calls per hour.
00:10
We know that it follows a poisson distribution, so the number of calls per hour is going to be distributed as poisson with lambda equal to 3.
00:20
We'll have that the probability that x equals a particular value, we'll call it k, is going to be equal to lambda to the power of negative lambda over k factorial.
00:35
So, to begin, for finding probability that x is equal to exactly 5, calculate that with my software over here, that's going to be, well, lambda is 3, so that would be 3 to the power of 5, or times, e to the power of negative 3 divided by 5 factorial.
00:55
So we get a result there of 0 .1008.
00:59
Then, for the second part of the problem, we're looking for the probability that x is less than or equal to 2.
01:08
So we can find that by calculating the probability that x equals 0, 1, and 2, and then we add up those values...